STINER: Automated Extraction of Strategic Cyber Threat Intelligence from X
This study addresses the challenge of extracting strategic-level Cyber Threat Intelligence (CTI) from informal social media text. We propose a fine-grained taxonomy tailored for strategic intelligence and construct the first expert-annotated threat alert corpus. Furthermore, we introduce a novel entity recognition framework integrating a DarkBERT domain-adaptive encoder with generative large language models. Experimental results demonstrate that this approach achieves an F1-score of 89.33%, significantly outperforming both general-purpose models and standalone LLMs. Notably, the system successfully provided early warnings for the SafePay ransomware campaign, validating its effectiveness and practical utility in efficiently extracting strategic CTI from complex, unstructured social media content.